The fact that your friend ordered the bark shredded may be the problem, shredded or powdered mimosa can be considered a precursor to the production of DMT. Which is, obviously, illegal. Nobody can tell you whether or not customs has seized your friends package but if. The parcel was seized, the fact that the bark was pre ground would be the prime reason. In the future note to your friend to only obtain the root in bark form and do ALL the preparations himself to avoid further seizings.